Tool/software: TINA-TI or Spice Models
Hello
I'm getting an irregular circuit error when I want to do a transient analysis and AC analysis. It shows a floating pin error at my capacitors but I connected it to the voltage generator, not sure why it would be floating. I want to find the frequency response of the circuit. Please see the image below for my circuit.
Thanks!
Hi Michelle,
This is related to not having a dc path to ground on your input when you run a transient sim. For a dc sim, the capacitors effectively look like open circuits and the input source does not factor in to the output voltage. I believe the way the dc operating point is calculated for a transient and ac sim is slightly different, and it is not able to reconcile the fact that your input source is floating. You can fix this by making your input a true differential signal with some common-mode level, or by adding a large resistor to ground on one of the source nodes as shown below.
